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Figure 7.33: gcl logic for rising edge, Figure 7.34: time chart for falling edge – B&B Electronics ADAM-6066 - Manual User Manual

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Chapter 7

Figure 7.33: GCL Logic for Rising Edge

7.

Falling Edge

For Falling Edge application, the DO value will be activated to logic
high, when DI value is changing from logic high to logic low (it is so-
called falling edge). But the DO value won’t continuously remain logic
high. Instead, after a specific period (in the example project, it is 1 sec-
ond), the DO value will back to logic low. Refer to Figure 7.34 below for
its time chart:

Figure 7.34: Time Chart for Falling Edge

AND

AND

Start Timer 0

If Timer 0 ≧ 1 s

Set Flag 0 = True

AND

If DI 0 = True

If DI 0 = True

If Flag 0 = False

Set DO 0 = True

Rule 1

Rule 2

Rule 3

DO 0

Time

T0

T1

T0 + 1 second

T1 + 1 second

DI 0

Falling Edge